Is Sewald Seattle's closer of the future?

ANAHEIM -- Among the Mariners’ misfit bullpen of non-roster invitees, Spring Training experiments and under-the-radar names, might they have uncovered their closer of the future?

It’s probably too early to say, but Paul Sewald has certainly made a case for that role. And depending on how the July 30 Trade Deadline plays out with Kendall Graveman, Sewald could be thrust into that spot sooner than later.

Entering Saturday, Sewald hadn’t surrendered an earned run since June 1, spanning 19 outings, over which the 64 batters he’s faced hit .102/.172/.119 with 29 strikeouts, five walks and six hits.

There was never a more high-leverage situation than the one encountered in Friday’s 6-5 win, when he took over after Graveman surrendered three unearned runs in the ninth inning, with Shohei Ohtani on first base, All-Star Jared Walsh at the plate and two outs. Sewald gave up a single to Walsh, who represented the winning run, but he came back to induce a flyout by Phil Gosselin to end the game.

It’s a spot that Mariners manager Scott Servais would’ve preferred to avoid, especially given that the pitching staff is down a roster spot with Héctor Santiago’s suspension. But that sequence encapsulated just how much trust a club teetering on contention has in a guy it signed on a Minor League flyer on Jan. 8.

“I would have already gone [to] arbitration and been a lot more successful with New York had I pitched this consistently for this long,” Sewald said. “This is definitely the most consistent I've been at the Major League level and I'm not taking it for granted. I'm just going out there and focusing on what I do really well, and just hammering that.”

Sewald has a 1.38 ERA and his 302 ERA+ (league average is 100) trails only eight other pitchers who’ve thrown at least 20 innings. In 26 outings since Sewald joined the Mariners on May 13, opposing hitters are batting .149/.238/.202 with 11 walks and 44 strikeouts.

Sewald’s 15.2 strikeouts-per-nine-innings ranks fifth in the Majors, and his 1.2 WAR, per FanGraphs, ranks 12th among relievers, which is saying something considering that just about every pitcher in front of him was on an Opening Day roster.

So, what’s exactly behind the rapid ascent of a guy who had a 5.50 ERA in 125 outings over four tough seasons with the Mets?

“The biggest change that I've had, I have just been flooded with confidence, from everyone top to bottom and how good they think I am,” Sewald said. “And if you get told that enough, then you start to believe it if you didn't.”

Specifically, Seattle’s front office raves about Sewald’s stuff. It saw a promising slider, wanted a closer look in Spring Training and then waited for a spot to install him to the 26-man roster once the regular season got going. His four-seam fastball that averages 92.4 mph has been his punchout pitch, but it’s set up by a bevy of breaking balls early in counts. In that sense, Sewald is almost pitching backwards.

“It's got a lot of sweep to it -- that ball is really breaking across the strike zone,” Servais said of Sewald’s slider. “What makes Paul so effective is his deception. He's throwing from a lower slot. The fastball is up shooting a little bit, and then the slider is coming right out of that tunnel, and it really is effective.”

The slider accounts for 43.4 percent of his usage, per Statcast, up from 33.3 percent in 2020, while his fastball is at 56.6 percent, right around last year’s rate. He basically ditched what was an admittedly poor changeup and focused exclusively on his best weapons at the urging of Seattle’s staff. Opposing hitters were teeing off against his heater in '20, with a .529 batting average and .824 slugging percentage. Now, those marks are .140 and .193, respectively.

His swing-and-miss rates are off the charts, and uncoincidentally, no hitter has homered off him this year. That’s precisely what teams look for in a closer, and Sewald now has a save in back-to-back outings. Perhaps it’s a foreshadowing for what the Mariners envision down the road.